Still picture television system

ABSTRACT

A system, by which a user can select a necessary frame by simplified arrangement using time-division still picture broadcast system. A natural still picture frame including a reference frame is repeatedly transmitted in a given order using the reference frame as a reference. A user apparatus detects the reference frame, and by counting number of the received frames, relationship of the frame to be displayed is confirmed, and the desired frame is displayed. For the information to select a frame, there are a case where only the information on the displayed still picture is displayed and a case where number of all still pictures transmitted within a period defined by the reference frame is displayed together with the information on the displayed still picture. For the still picture frame information to be inserted in an audio band, there are the following three cases: a case where it is inserted only in an audio band corresponding to the reference still picture, a case where it is inserted in an audio band corresponding to some of the still pictures, and a case where an identification signal is inserted in an audio band corresponding to each of the still pictures. For the still picture frame information to be inserted in the audio band, there are the following three cases: a case where an audio signal is inserted in a main audio band, a case where it is inserted in a second audio band, and a case where other adequate control signal is inserted in a sub audio band

FIELD OF THE INVENTION

The present invention relates to interactive value added informationservices, which are offered by television broadcasting such asterrestrial wave broadcasting, CATV, or satellite broadcasting, etc. andtelephone, and in particular to a system for providing an interactiveinformation service by combining picture media for television such asstill picture television broadcasting, still picture video tape, stillpicture video disk, etc. with a telephone.

BACKGROUND ART

In the information-oriented society of today, various transmitting meansare used to transmit electrical and electronic information such assound, picture, text data, binary data, etc. Of such electrical andelectronic information, low quality sound, monochrome still picture atlow speed, character data at low speed, and binary data at low speed aretransmitted by public telephone line as electric signals, and monochromestill picture at high speed, character data at high speed and binarydata at high speed are transmitted by ISDN (Integrated Services DigitalNetwork) line as an electric signal. High quality sound and movingpicture are transmitted by terrestrial wave broadcasting, satellitebroadcasting or CATV as a modulated radio wave or by optical fiber asmodulated light.

In the present information-centered era, attention is now focused oninteractive information systems as a promising major information systemin future. The interactive information system is a system, in whichinformation is selectively received and positively utilized by thegeneral public, who, hitherto, have been merely receivers of the one-wayinformation sent to them.

Interactive information systems currently used are answering systemsusing an automatic voice response system via public telephone line,videotex systems represented by CAPTAIN (Character And Pattern TelephoneAccess Information Network) using still picture, and VRS (Video ResponseSystem) using moving picture via dedicated line.

Of these interactive information systems, the answering system isdisadvantageous in that sufficient information cannot be obtainedbecause it depends upon audio information only and that input and outputdata cannot be visually confirmed.

The videotex system has drawbacks in that there is a limitation in thecontents to be displayed because texts and pictures are displayed byusing character codes, and the picture information using character codesprovides a smaller amount of information than a natural picture.

The VRS system has no limitation in the contents of display because anatural moving picture can be used, while communication cost isexpensive because a wide band dedicated line must be used.

On the other hand, various information services such as televisionshopping, application or subscription, weather forecast, trafficinformation, etc. are offered in the currently used television system,although these are not interactive. Most of the picture informationneeded in these information services is still picture information, andmoving picture information is needed in very rare cases. Thus, in thecurrent television system offering these information services, a stillpicture is broadcast as moving picture. Specifically, by transmittingseveral hundreds to several thousands of the same picture, a stillpicture is displayed on a television set.

Therefore, the transmitting cost of the still pictures is veryexpensive, and an interactive information service for transmitting stillpictures to match the demand of the users is not currently available.

For example, television shopping is one of the information servicesusing pictures. However, in the television shopping practiced to date,only the one-way product information, transmitted by the broadcastingstation, is utilized, and interactive information service in which thedesired picture from product information is displayed on the televisionset according to the intention of the users and the users carry outshopping based on the contents of the display is not practicallyavailable.

A television picture is composed of frame units. In the NTSC systemadopted in Japan, the picture is sent at a rate of 30 frames per second.If one still picture is transmitted for each frame, 30 natural stillpictures are transmitted within a second.

As a still picture broadcasting system based on this principle, there isa system called the "time-division still picture broadcast system".

FIG. 1 represents a drawing to explain the time-division still picturecommunication system.

In the time-division still picture broadcast system shown in FIG. 1,still pictures 3-1, 3-2, 3-3, 3-4 . . . are photographed at first byindependent television cameras 4-1, 4-2, 4-3, 4-4 . . . at a stillpicture broadcasting station 1. Next, these still pictures are composedto television signals comprising frames 5-1, 5-2, 5-3, 5-4 . . . , andthese are transmitted to still picture receiving devices 2-1, 2-2, 2-3,2-4 . . .

Upon receipt of the television signals, necessary frames are stored atframe memories 6-1, 6-2, 6-3, 6-4, . . . at the still picture receivingdevices. Next, the stored frames are repeatedly read out from the framememories and are displayed on display units 7-1, 7-2, 7-3, 7-4 . . . asstill pictures.

Selection of the necessary frames and recording them to the framememories are carried out by the procedure such as inserting a frameidentification signal to the horizontal scanning line during thevertical retrace interval of each frame.

In one frame, two field pictures comprising different picture componentsare superimposed by interlace scanning.

Each of the frame pictures is a complete natural picture, while a fieldpicture is not a complete natural picture because its amount ofinformation is only one-half of that of the natural picture. However,when compared with the picture based on character codes, it may bereferred as a natural picture, which provides satisfaction. In abroadcast of still pictures, twice as many field pictures aretransmitted.

An interactive still picture information service system has beenproposed, in which a still picture information service is requested by,for example, a public line and the still picture information service isoffered by the "time-division still picture broadcast system" inresponse to such request. FIG. 2 shows a general outline of the system.

This system comprises a still picture broadcasting station apparatus 8for broadcasting a still picture by the time-division still picturebroadcast system, an information provider apparatus 9, a user apparatus10, and a data communication device such as a telephone set 15. Aterrestrial broadcasting wave 12 or satellite broadcasting wave or CATVradio wave is used to connect between the still picture broadcastingstation apparatus 8 and the user apparatus 10, and a communication line11 such as public line or CATV line is used to connect the telephone set15 with the information provider apparatus 9. A communication line suchas public line or dedicated line is used to connect the informationprovider apparatus 9 with the still picture broadcasting stationapparatus 8.

The information provider apparatus 9 may not be used. In this case, thestill picture broadcasting station apparatus 8 is directly connectedwith the user apparatus 10 via a communication line such as a publicline or a dedicated line.

The user apparatus 10 comprises a set-top box 14 for receiving the stillpicture, a display unit 13 and a data communication device such as atelephone set 15. The set-top box 14 is connected to a televisionantenna for receiving the still picture broadcast, a television antennafor receiving a satellite broadcast, or a coaxial cable for CATV. Theset-top box 14 is connected to the display unit 13 such as a televisionset. The telephone set 15 is connected to a communication line 11 suchas a public line or CATV line.

In this system, when a user wishing to receive the information service,calls the information provider apparatus 9 using the telephone set 15via the communication line 11 and requests transmission of the desiredstill picture, the request is transferred to the still picturebroadcasting station apparatus 8. As a result, the desired still picture16 is broadcast, and the desired still picture 17 is displayed on thedisplay unit 13 by the user.

In the interactive still picture information service system as describedabove, selection of necessary frames and recording of them in framememories are performed in such a manner that a frame identificationsignal is inserted into the horizontal scanning line in a verticalretrace interval of each frame by the still picture broadcasting stationapparatus 8, and this frame identification signal is detected by theuser apparatus 10.

For this purpose, it is necessary to provide means for inserting theframe identification signal to the horizontal scanning line in thevertical retrace interval of each frame at the still picturebroadcasting station apparatus 8 and also to provide the user apparatus10 with means for detecting the frame identification signal. Thisnaturally means that the still picture broadcasting station apparatus 8and the user apparatus 10 will be more complicated.

DISCLOSURE OF THE INVENTION

To solve the above problems, it is an object of the present invention toprovide an interactive information service system, which adopts a"time-division still picture broadcast system" as the informationtransmitting means and uses a public line as a data communication means,whereby the user can select a necessary frame by a simple arrangement.

The system of the present invention comprises an information serviceprovider apparatus, a user apparatus, a television signal path forconnecting the information service provider apparatus with the userapparatus, and a communication path such as a line.

The information service provider apparatus comprises a still picturetelevision signal transmitter for transmitting natural still pictures bythe time-division still picture broadcast system and a datacommunication device for performing data communication with the user.

The user apparatus comprises a still picture television receiver forreceiving and displaying a natural still picture television signaltransmitted by the time-division still picture broadcast system and adata communication device connected to a communication line via thestill picture television receiver for performing data communication withthe information service provider.

A terrestrial broadcasting wave, satellite broadcasting wave or CATVline are used for the television signal path, and a public line, ISDNline or CATV line is used as the communication line.

The natural still picture frame including the reference frame isrepeatedly transmitted in a given order using the reference frame as areference. The user apparatus detects the reference frame and counts thenumber of received frames. As a result, the relationship of the desiredframe is confirmed and the desired frame is displayed.

To transmit information for selecting the frames, the following methodsare used instead of the prior art method of inserting a frameidentification signal to the horizontal scanning line in a verticalretrace interval: insert still picture frame information to thedisplayed still picture; insert still picture frame information to theaudio band; and insert the frame information to one of horizontalscanning line, still picture or audio band.

The number of still pictures to be repeatedly transmitted is fixed insome cases, semi-fixed in some cases, or variable in some other cases.

In one embodiment, information relating to the still picture framedisplayed is inserted into the still picture, and in another embodiment,the number of all the still pictures transmitted in a period defined bythe reference frame is displayed together with the information on thedisplayed still picture.

For the still picture frame information to be inserted in the audioband, there are the following three cases: a case where it is insertedinto an audio band corresponding to the reference still picture, a casewhere it is inserted in an audio band corresponding to some stillpictures, and a case where it is inserted into audio band correspondingto all still pictures.

For the still picture frame information to be inserted into the audioband, there are the following three cases: an audio signal is insertedinto the main audio band; an audio signal is inserted into a sub audioband; and an adequate control signal is inserted into a sub audio band.

The information other than the natural still pictures necessary for theinteractive communication is transmitted or received via thecommunication line, and it is converted to a character pattern by acharacter generator incorporated in the still picture televisionreceiver of the user. Further, it is stored in frame memory of the userapparatus after being superimposed with the natural still picture, andthe superimposed pictures are repeatedly read and displayed on a displayunit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a drawing to explain a time-division still picture broadcastsystem;

FIG. 2 is a drawing of a still picture broadcast system;

FIGS. 3(a) to 3(d) represent a still picture television system of firstand second embodiments of the present invention;

FIGS. 4(a) to 4(d) represent a still picture television system of athird embodiment of the present invention;

FIGS. 5(a) to 5(e) represent a still picture television system of fourthand fifth embodiments of the present invention;

FIGS. 6(a) to 6(c) represent a still picture television system of asixth embodiment of the present invention;

FIGS. 7(a) to 7(c) represent a still picture television system of aseventh embodiment of the present invention;

FIG. 8 represents a still picture television system of an eighthembodiment of the present invention;

FIG. 9 represents a still picture television system of a ninthembodiment of the present invention;

FIG. 10 shows a still picture television system used in a tenthembodiment of the present invention; and

FIGS. 11(a) to 11(c) represent a still picture television system of thetenth embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

In the following, description will be given of embodiments of thepresent invention referring to the accompanied drawings.

To facilitate explanation, the embodiments are divided into thefollowing three cases: a case where frame information is displayed on astill picture, a case where the frame information is inserted into anaudio band, and a case where the frame information is inserted into noneof the horizontal scanning line, still picture or audio band. Each ofthese three cases are further divided into a case where the number ofstill pictures for a period is fixed, a case where it is semi-fixed, anda case where it is variable.

[Embodiment 1]

Referring to FIG. 3, description will be given on the operation of anembodiment of a system where frame information is displayed on stillpictures and the number of the still pictures to be transmitted isfixed. In this system, a conventional type apparatus as shown in FIG. 2is used.

In this system, as shown in FIG. 3(a), a still picture broadcastingstation 8 makes up a set of a fixed number of still pictures, e.g. 100still pictures such as 21, 22, 23, 24, 25 . . . , puts a frame number toeach of the still pictures and transmits them repeatedly. In this case,a still picture 21 having frame number 1 is used as a main menu picture,but this menu picture is not necessarily required.

A set-top box 14 for receiving the still picture detects a desiredframe, and its still picture 23 is displayed on the display unit 13. Inthis still picture, a still picture frame number 28 is displayed as"15", for example, as shown in FIG. 3(b).

The set-top box 14 for receiving the still picture starts to count thenumber of frames after the received still picture. In this case, a stillpicture having a frame number which is obtained by subtracting aninteger multiple of 100 from the number of counts, is the same pictureas the displayed still picture. Accordingly, the counter of the set-topbox 14 for receiver of still picture is reset at every 100 counts.

Also, a frame having a frame number 1 and being next to a frame having aframe number 100 is a frame of a main menu picture. Therefore, a framenext to a frame having a number, which is obtained by subtracting thedisplayed frame number 15 from the total frame number 100, i.e. a frameafter 86 counts, is a frame of the main menu picture 21.

When the user inputs "15" to the set-top box 14 for receiving the stillpicture, a menu picture 21 having the frame number 26 which is displayedas "1", meaning that it is a menu picture, is displayed on the displayunit 13 as shown in FIG. 3(c). This is the frame after 86 counts, whichis obtained by subtracting the displayed frame number 15 from the totalframe number 100 and by adding 1.

Also, the menu picture may comprise a main menu picture and a sub-menupicture.

When a frame number "67" of a desired still picture 24, as shown in FIG.3(d), is inputted to the receiver 14 based on the data of the menupicture 21, the set-top box 14 for receiving the still picture searchesto display a still picture 24, which is specified according to a framenumber counted by the same procedure as in the case where the main menuis displayed.

Some of the still picture information to be offered such as weatherinformation, stock market information, traffic information, etc. may bebetter broadcast regardless of whether the user wants it or not.

The system is designed in such a manner that the still pictureinformation as described above can be selected from the main menupicture or from the upper-level sub-menu picture.

[Embodiment 2]

Description will now be given on the operation of an embodiment wherethe frame information is displayed on still pictures and the number ofthe still pictures to be transmitted is semi-fixed. The arrangement ofthe still pictures in this embodiment is the same as in Embodiment 1,and description will be given referring to FIG. 3.

In this system, as shown in FIG. 3(a), the still picture broadcastingstation 8 makes up a set of a fixed number of still pictures, e.g. 90still pictures such as 21, 22, 23, 24, 25 . . . , puts a frame number toeach of the still pictures, and transmits them repeatedly. In this case,a still picture 21 having frame number 1 is regarded as a menu picture,but this menu picture is not necessarily required.

The number of the still pictures to be transmitted is a semi-fixednumber, which varies according to the conditions of broadcasting. Thisnumber, e.g. 90, is notified in advance by other publicity informationtransmitting means such as newspaper or by individual informationtransmitting means such as a telephone line.

The user inputs in advance the data on the number of still picturesobtained from these information transmitting means to the set-top box 14for receiving the still picture.

As shown in FIG. 3(b), the set-top box 14 detects an adequate frame, andits still picture 23 is displayed on the display unit 13. On this stillpicture, a still picture frame number 28 is displayed as "15", forexample.

The set-top box 14 for receiving the still picture starts to count thenumber of frames after the received still picture. In this case, thestill picture having a frame number, which is obtained by subtracting aninteger multiple of 90 from the number of counts, is the same picture asthe displayed still picture. Accordingly, the counter of the receiver 14is reset at every 90 counts.

Also, a frame having a frame number 1 and being next to a frame having aframe number 90 is the frame of the main menu picture. Therefore, aframe next to the number, which is obtained by subtracting the displayedframe number 15 from the total frame number 90, i.e. a frame after 76counts, is the frame of the main menu picture 21.

When the user inputs "15" to the set-top box 14 for receiving the stillpicture, a main menu picture 21 having a frame number 26 displayed as"1" is displayed on the display unit 15 as shown in FIG. 3(c), meaningthat it is a menu picture. This is a frame after 76 counts, which isobtained by subtracting the display frame number 15 from the total framenumber 90 and by adding 1.

Also, the menu picture may comprise a main menu picture and a sub-menupicture.

When a frame number "67" of a desired still picture 24, as shown in FIG.3(d), is inputted to the set-top box 14 for receiving the still picturebased on the data of the menu picture 21, the set-top box 14 forreceiving the still picture searches and displays the specified stillpicture 24 according to the frame number counted by the same procedureas in the case where the main menu is displayed.

Some of the still picture information to be offered such as weatherinformation, stock market information, traffic information, etc. may bebetter broadcast regardless of whether the user wants it or not.

The system is designed in such a manner that the still pictureinformation as described above can be selected from the main menupicture or from the upper-level sub-menu picture.

[Embodiment 3]

Description will be given below on operation of a system of anembodiment where frame information is displayed on still pictures andthe number of still pictures to be transmitted is variable, referring toFIG. 4.

In this system, the conventional apparatus as shown in FIG. 2 is alsoused.

As shown in FIG. 4(a), the still picture broadcasting station makes up aset of an adequate number of still pictures, e.g. 100 still picturessuch as 31, 32, 33, 34, 35, . . . puts a frame number to each of thestill pictures, and transmits them repeatedly. In this case, the framenumber also contains information on the total number of still pictures.

In this case, the first still picture is regarded as a menu picture, butthis menu picture is not necessarily required.

The set-top box 14 for receiving the still picture detects an adequateframe and displays its still picture 33 and starts to count the numberof frames after the displayed still picture.

As shown in FIG. 4(b), the frame number of the still picture and thetotal number of all the transmitted still pictures, e.g. 15 and 100, aredisplayed on the received still picture as "15100", as shown byreference numeral 38 in the Figure.

Alternatively, the display may be, for example, "10015", "115/100","15-100", etc.

The user inputs "15100" to a controller of the receiver 14.

Where 100 still pictures are repeatedly transmitted, the still picturehaving a frame number, which is obtained by subtracting an integermultiple of 100 from the number of counts, is the same picture as thedisplayed still picture. Therefore, if the user inputs "15100",information that the total number of still pictures is 100 is inputtedto the user apparatus because the latter half of the inputted numberinputted to the user apparatus is "100".

When the total number of still pictures is inputted, the user apparatussubtracts an integer multiple of 100 from the number of counts, and thecounter is reset at every 100 counts.

A frame having a frame number 1 and being next to a frame having a framenumber 100 is the frame of the main menu picture. Accordingly, a framenext to the number, which is obtained by subtracting the displayed framenumber 15 from the total frame number 100, i.e. a frame after 86 counts,is the frame of the menu picture 31.

When the user inputs "15100" to the set-top box 14 for receiving thestill picture, a menu picture 31 having a frame number 36 which is isdisplayed as "1100", meaning that it is the menu picture, is displayedon the display unit 15 as shown in FIG. 4(c). This is the frame after 86counts, which is obtained by subtracting the display frame number 15from the total frame number 100 and by adding 1.

Also, the menu picture may comprise a main menu picture and a sub-menupicture.

When the frame number "67100" of the desired still picture as shown inFIG. 4(d) is inputted to the receiver 14 based on the data of the menupicture 31, the receiver 14 searches to display the specified stillpicture 34 according to the frame number counted by the same procedureas in the case where the main menu is displayed.

Some of the still picture information to be offered such as weatherinformation, stock market information, traffic information, etc. may bebetter broadcast regardless of whether the user wants it or not.

It is designed in such a manner that the still picture information, asdescribed above, can be selected from the main menu picture or from theupper-level sub-menu picture.

[Embodiment 4]

FIG. 5 shows a method to detect a specific picture such as a menupicture by arranging not a character signal but a section of the picturehaving a specific hue or luminance.

The conventional apparatus as shown in FIG. 2 may be modified and used.

As shown in FIG. 5(a), the still picture broadcasting station 8 makes upa set of an adequate number of still pictures, e.g. 100 still picturessuch as 41, 42, 43, 44, 45, . . . , then, as shown by 46 in FIG. 5(b), asection having a specific hue or luminance is arranged on a part of aspecific still picture frame 41 (hereinafter referred as "referenceframe"), and these are repeatedly transmitted.

In this case, the still picture of the reference frame 41 is regarded asa menu picture, but this menu picture is not necessarily required.

The set-top box 14 detects the reference frame 41 based on the referenceframe signal 46, displays a menu picture as the reference frame 41 onthe display unit 13, as shown in FIG. 5(b), and starts to count thenumber of the subsequent frames.

Also, the menu picture may comprise a main menu picture and a sub-menupicture.

The counter of the frame number is reset each time the reference framenumber 46 is received.

When the user inputs the frame number of the desired still picture tothe receiver 14 based on the data of the menu displayed as the referenceframe 41 on the display unit 13, the receiver searches the specifiedpicture according to the number of frames counted, and the desired stillpicture 44 is displayed on the display unit 13 as shown in FIG. 5(c).

Based on the reference frame signal 46, the frame counter is started,and the number of counts until the next reference frame signal isreceived is the total frame number.

Therefore, even when the number of frames is variable, it is possible inthis case to identify the total frame number.

Some of the still picture information to be offered such as weatherinformation, stock market information, traffic information, etc. may bebetter broadcast regardless of whether the user wants it or not.

If the relationship of the still picture information with the referenceframe is kept at constant level, the still picture can be selectedwithout using the main menu.

[Embodiment 5]

FIGS. 5(d) and (e) represent variations of Embodiment 4, and referencenumerals 41' and 41" represent a first field and a second fieldrespectively, which constitute a frame 41.

The frame number in this case is different between the first field andthe second field. This contributes to easier identification.

[Embodiment 6]

Referring to FIG. 6, description will be given on the operation of anembodiment where the still picture frame information is inserted into anaudio band and it is inserted into the audio band corresponding only toa specific still picture. In this system, the conventional typeapparatus, as shown in FIG. 2, can be modified and used.

In FIG. 6(a), reference numeral 50 represents a still picture program,and 56 represents an audio band to be broadcast together with the stillpicture program.

The still picture broadcasting station 8 makes up a set of an adequatenumber of still pictures, e.g. 100 still pictures such as 51, 52, 53,54, 55 . . . A signal 57 (hereinafter referred to as "reference framesignal") is inserted at a point to correspond to a specific stillpicture frame 51 (hereinafter referred to as "reference frame") in theaudio band 56, e.g. at the position of a vertical synchronizing signalto be repeatedly transmitted.

In this case, the still picture of the reference frame 51 is regarded asa menu picture, but this is not necessarily required.

The reference frame signal 57 may be sound inserted in a main audioband, or it may be inserted in a sub audio band, or it may be a controlsignal other than sound inserted in the sub audio band.

The set-top box 14 for receiving the still picture detects the referenceframe 51 based on the reference frame signal 57 inserted in the audioband, displays the menu picture of the reference frame 51 on the displayunit 13, as shown in FIG. 6(b), and starts to count the number of thesubsequent frames.

Also, the menu picture may comprise a main menu picture and a sub-menupicture.

The counter of the number of frames is reset each time the referenceframe signal 57 is received.

When the user inputs the frame number of the desired still picture tothe receiver 14 based on the data of the display menu displayed as thereference frame 51 on the display unit 13, the receiver searches for thespecified picture according to the number of the counted frames anddisplays it on the display unit 13, as shown in FIG. 6(c).

By the reference frame signal 57, the frame counter is started, and thenumber of counts until the next reference frame signal is received isthe total number of frames.

Therefore, the total number of frames can be identified even when thenumber of frames is variable.

Some of the still picture information to be offered such as weatherinformation, stock market information, traffic information, etc. may bebetter broadcast regardless of whether the user wants it or not.

If the relationship of the still picture information with the referenceframe is kept at a constant level, it is possible to select the stillpicture without using the main menu.

When the reference frame signal 57 is inserted into the main audio band,the reference frame signal 57 is heard by the user as sound.

To avoid this, the reference frame signal 57 should be inserted into thesub audio band.

In such a case, a control signal other than sound may be used as thesignal to be inserted into the sub audio band.

In a television set, the picture signal and the audio signal areprocessed separately, and even when it is tried to use the signalinserted in the audio band as a control signal to select the stillpicture, it may not be successfully controlled.

In such a case, the signal inserted in the audio band should betransmitted at an earlier time than the corresponding still pictureframe.

[Embodiment 7]

Description will now be given on operation of an embodiment where stillpicture frame information is inserted only in the audio band, whichcorresponds to some of the still pictures.

In FIG. 7(a), reference numeral 60 represents a still picture program,and 66 represents an audio band, which is broadcast together with thestill picture program.

The still picture broadcasting station 8 makes up a set of an adequatenumber of still pictures, e.g. 100 still pictures such as 61, 62, 63,64, 65 . . . A signal 67 (hereinafter referred to as "reference framesignal") is inserted at a point corresponding to a specific stillpicture frame 61 (hereinafter referred to as "reference frame") in theaudio band 66, e.g. at the position of the vertical synchronizingsignal, and a signal 68 (hereinafter referred to as "sub-reference framesignal") is inserted at a point corresponding to some of the stillpicture frames 62 . . . (hereinafter referred to as "sub-referenceframe"), e.g. at the position of the vertical synchronizing signal, andthese are transmitted repeatedly.

In this case, the still picture of the reference frame 61 and the stillpicture of the sub-reference frame 62 are regarded as a menu picture anda sub-menu picture, but other pictures may also be displayed.

When the reference frame signal 67 and the sub-reference frame signal 68are inserted in the audio band, there are the following three cases: acase where these are sound signals inserted in the main audio band, acase where they are sound signals inserted in the sub audio band, and acase where they are control signals other than sound inserted in the subaudio band.

The reference frame signal and the sub-reference frame signal aresignals identifiable, i.e. distinguishable, from each other.

The set-top box 14 for receiving the still picture detects a referenceframe 61 based on the reference frame signal 67 inserted in the audioband and a sub-reference frame 62 based on the sub-reference framesignal 68, and displays a main menu picture 61, i.e. a reference framepicture, and a sub-menu picture 62, i.e. a sub-reference frame picture,on the display unit 13, as shown in FIG. 7(b), and starts to count thenumber of the subsequent frames.

The count of the number of frames is reset each time the reference framesignal 67 is received.

When the user inputs to the receiver 14 the frame number of the desiredstill picture, based on the data of the main menu picture 61 or on thedata of the sub-menu picture 62 displayed on the display unit 13, thereceiver searches the specified picture according to the number of thecounted frames and displays it on the display unit 13 as shown in FIG.7(c).

By the reference frame signal 67, the frame counter is started, and thenumber of counts until the next reference frame signal is received isthe total number of frames.

Therefore, it is possible in this case to identify the total number offrames even when the number of frames is variable.

If the relationship on the still picture information with the referenceframe is kept at a constant level or if the still picture displayed onthe sub-reference frame is the sub-menu picture, it is possible toselect the still picture without using the menu.

If the still picture program is arranged in a plurality of groups and areference frame is provided for each of these groups, and if a referenceframe signal having a different form is used for each of a plurality ofreference frames, a single still picture broadcasting station cantransmit a plurality of still picture programs at the same time.

When the reference frame signal 67 or the sub-reference frame signal 68is inserted into the main audio band, the reference frame signal 67 orthe sub-reference frame signal 68 is heard by the user as sound.

To avoid this, the reference frame signal 67 or the sub-reference framesignal 68 should be inserted into the second audio band.

In such a case, an adequate control signal other than sound may be usedas a signal inserted in the sub audio band.

In a television set, the picture signal and the audio signal areseparately processed. Accordingly, even when it is tried to use thesignal inserted into the audio band as the control signal for selectingthe still picture, it may not be successfully controlled.

In such a case, the signal inserted in the audio band should betransmitted at an earlier time than the corresponding still pictureframe.

If it is designed in such a manner that the sub-reference frame signalis regarded as a specific signal and a still picture having this signalcannot be used in the general user apparatus, it is possible to transmitthe sub-reference frame still picture only to a specific user or aspecific group of users, and secrecy can be kept for instances such astelevision shopping.

[Embodiment 8]

Description will be given now on operation of a system of an embodimentwhere still picture frame information is inserted in an audio band tocorrespond to all still pictures.

FIG. 8 shows an embodiment where still picture frame information isinserted in the main audio band corresponding to all still pictures.Reference numeral 70 represents a still picture program, and 75indicates a main audio band to be broadcast together with the stillpicture program.

The still picture broadcasting station 8 makes up a set of an adequatenumber of still pictures, e.g. 100 still pictures such as 71, 72, 73 . .. Signals 76, 77, 78 . . . are inserted at points in the main audio band75 corresponding to each of the still picture frames, e.g. at theposition of the vertical synchronizing signal, and are repeatedlytransmitted.

In this case, the reference frame signal 76 to be inserted at a pointcorresponding to a specific reference frame 71 may be made differentfrom the signal to be inserted at points corresponding to the otherframes.

The set-top box 14 for receiving the still picture detects a referenceframe 71 based on the reference frame signal 76 inserted in the audioband, displays a main menu picture 71, i.e. its reference frame picture,on the display unit 13, and starts to count the number of the subsequentframes.

The count of the number of frames is reset each time the reference framesignal 76 is received.

When the user inputs to the receiver 14 the frame number of the desiredstill picture, based on the data of the main menu picture 71 displayedon the display unit 13, the receiver searches the specified pictureaccording to the number of the counted frames, and displays it on thedisplay unit 13.

By the reference frame signal 76, the frame counter is started, and thenumber of counts until the next reference frame signal is received isthe total number of frames.

Therefore, it is possible in this case to identify the total number offrames even when the number of frames is variable.

If the relationship on the still picture information with the referenceframe is kept at constant level or if the still picture displayed on thesub-reference frame is the sub-menu picture, it is possible to selectthe still picture without using the menu.

If the still picture program is arranged in a plurality of groups, and areference frame is provided to each of these groups and a referenceframe signal having a different form is used for each of a plurality ofreference frames, a single still picture broadcasting station cantransmit a plurality of still picture programs at the same time.

[Embodiment 9]

FIG. 9 shows an embodiment where a signal corresponding to a stillpicture frame is inserted into the main audio band and the sub audioband. Reference numeral 80 represents a still picture program, and 84represents the main audio band and 85 the sub audio band which arebroadcast together with the still picture program.

The still picture broadcasting station 8 makes up a set of an adequatenumber of still pictures, e.g. 100 still pictures such as 81, 82, 83 . .. A reference frame signal 86 is inserted at a point in the main audioband 84 corresponding to the reference frame 81, e.g. at the position ofvertical synchronizing signal, and signals 87, 88, 89, . . . areinserted at each of the points in the sub audio band corresponding toeach of the still pictures, e.g. at the position of verticalsynchronizing signal, and these are repeatedly transmitted.

The set-top box 14 for receiving the still picture detects the referenceframe 81 based on the reference frame signal 86 inserted in the mainaudio band, displays a main menu picture, i.e. the reference framepicture, on the display unit 13, and starts to count the number of thesubsequent frames.

The count of the number of frames is reset each time the reference framesignal 86 is received.

When the user inputs to the receiver 14 the frame number of the desiredstill picture, based on the data of the main menu picture displayed onthe display unit 13, the receiver searches the specified pictureaccording to the number of the counted frames, and displays it on thedisplay unit 13.

By the reference frame signal 86, the frame counter is started, and thenumber of counts until the next reference frame signal is received isthe total number of frames.

Therefore, it is possible in this case to identify the total number offrames even when the number of frames is variable.

If the relationship on the still picture information with the referenceframe is kept at constant level or if the still picture displayed on thesub-reference frame is the sub-menu picture, it is possible to selectthe still picture without using the menu.

[Embodiment 10]

Description will now be given on a system of an embodiment where frameinformation is not inserted in any of the horizontal scanning line, thestill picture or the audio band.

In this embodiment, still picture frame information is not inserted inthe still pictures transmitted from the still picture broadcastingstation. It is transmitted via public line, or where still pictures arebroadcast via CATV, it is transmitted via CATV line.

Therefore, an audio signal or an adequate control signal other than theaudio signal is used as in the case of still picture frame informationinserted in the sub audio band.

FIG. 10 shows an arrangement of a system according to the presentinvention. This system comprises a still picture broadcasting stationapparatus 90 for broadcasting a still picture by time-division stillpicture broadcast system, an information service provider apparatus 91,a user apparatus 92 and a data communication device such as a telephone97. The still picture broadcasting station apparatus 90 communicateswith the user apparatus 92 via terrestrial broadcasting path, satellitebroadcasting path or CATV path 94. The telephone 97 is connected withthe information service provider apparatus 91 via a communication line93 such as a public line or CATV line. The information service providerapparatus 91 is connected with the still picture broadcasting stationapparatus 90 via a communication line such as a public line or adedicated line.

The information service provider apparatus 91 may not be used. In thiscase, the still picture broadcasting station apparatus 90 is directlyconnected with the user apparatus 92 via the communication line 93 suchas public line or dedicated line.

The user apparatus 92 comprises a set-top box 96 for receiving the stillpicture and a display unit 95. A television antenna for receivingsatellite broadcasting or a coaxial cable for CATV is connected to theset-top box 96. The set-top box 96 for receiving the still picture isconnected to a display unit 95 such as a television set. Thecommunication line 93 is connected with the telephone 97 indirectly viathe set-top box 96 for receiving the still picture.

In this embodiment, the reference frame signal is not inserted in thesynchronizing signal of the still picture or in the audio band, but itis transmitted, for example, as a dual-tone signal, via thecommunication line. To utilize the dual-tone signal transmitted via thecommunication line, it is necessary to capture the signal in the set-topbox 96. For this purpose, the communication line 93 is directlyconnected to the set-top box 96 and the telephone 97 is indirectlyconnected with the communication line 93 via the set-top box 96.

Next, description will be given on the operation of the system of theFIG. 10 embodiment, referring to FIG. 11.

In FIG. 11(a), reference numeral 100 represents a still picture program,and 106 indicates an audio signal transmitted via the communicationline.

The still picture broadcasting station 90 makes up a set of an adequatenumber of still pictures, e.g. 100 still pictures such as 101, 102, 103,104, 105 . . . , and transmits them repeatedly.

On the other hand, the information service provider apparatus 91synchronizes the reference frame dual tone multi frequency (DTMF) signal107 with the reference frame and transmits it to the set-top box 96 forreceiving the still picture via the communication line.

In this case, the still picture of the reference frame 101 is regardedas a menu picture, but this menu picture is not necessarily required.

The set-top box 96 detects the reference frame 101 based on the receivedreference frame DTMF signal 107, displays the menu picture, i.e. thereference frame 101, on the display unit 95, as shown in FIG. 11(b), andstarts to count the number of the subsequent frames.

The menu picture may comprise a main menu picture and a sub-menupicture.

The count of the number of frames is reset each time the reference frameDTMF signal 107 is received.

When the user inputs the frame number of the desired still picture tothe set-top box 96 for receiving the still picture by DTMF signal of thetelephone based on the data of the menu displayed as the reference frame101 on the display unit 95, and the set-top box 96 searches for thespecified picture according to the number of the counted frames, anddisplays the specified still picture 104 on the display unit 95, asshown in FIG. 11(c).

By the reference frame DTMF signal 107, the frame counter is started,and the number of counts until the next reference frame signal isreceived is the total number of frames.

Therefore, it is possible to identify the total number of frames evenwhen the number of frames is variable.

Some of the still picture information to be offered such as weatherinformation, stock market information, traffic information, etc. may bebetter broadcast regardless of whether the user wants it or not.

If the relationship on the still picture information with the referenceframe is kept at a constant level or if the still picture displayed onthe sub-reference frame is the sub-menu picture, it is possible toselect the still picture without using the menu.

In addition to a system where frame information is not inserted to anyof the horizontal scanning line, the still picture, or the audio band,there is alternatively a system where the still picture frameinformation is inserted only in the audio band corresponding to some ofthe still pictures or a system where still picture frame information isinserted to the audio band corresponding to all of the still pictures.However, the operation in these latter systems is not basicallydifferent from the operation in the system of Embodiments 5 or 6, anddetailed description is not given here.

In the above, description has been given on the cases where the systemof the present invention is applied in still picture televisionbroadcasting, whereas it is needless to say that the present inventionis also applicable to a video tape or a video disk where still picturesare recorded.

INDUSTRIAL APPLICABILITY

The present system is an interactive information service system using atelephone and a television set widely propagated for home use, and theburden of cost on general users is low.

Pictures different for each frame of a television picture signal aretransmitted, and this makes it possible to broadcast a great number ofstill pictures within a short time. For this reason, it is possible toprovide interactive still picture services to each of many users.

Also, it is possible to display the contents of communication performedbetween the user and the information service provider on the displayunit without increasing the burden on the information service provider.

I claim:
 1. A method of transmitting a plurality of still pictures by atime-division still picture broadcast system, including the steps ofdetermining a still picture to serve as a reference still picture, andselecting a still picture which has a relationship with said referencestill picture, and appending still picture information to saidtransmitted still pictures for display at a receiver end.
 2. A methodaccording to claim 1, wherein said still pictures are transmitted in aunit of frames.
 3. A method according to claim 1, wherein said stillpictures are transmitted in a unit of fields.
 4. A method according toclaim 1, wherein said reference still picture is transmittedperiodically.
 5. A method according to claim 1, wherein said stillpictures are repeatedly transmitted.
 6. A method according to claim 1,wherein a plurality of groups of still picture programs comprising saidreference still picture and said still picture having said relationshipwith said reference still picture are transmitted in series and alsosaid plurality of groups of still picture programs are repeatedlytransmitted.
 7. A method according to claim 1, wherein still pictureinformation is appended to said transmitted still pictures for displayat a receiver end.
 8. A method according to claim 1, wherein the orderof said still pictures is displayed as said still picture information.9. A method according to claim 1, wherein the order of said stillpictures and the total number of still pictures repeatedly transmittedare displayed as said still picture information.
 10. A method accordingto claim 1, wherein said still picture information is displayed only ona specific still picture among the transmitted still pictures.
 11. Amethod according to claim 1, wherein said still picture information isinserted in an audio band, which is transmitted together with said stillpictures.
 12. A method according to claim 11, wherein said still pictureinformation is inserted in an audio band corresponding to all stillpictures.
 13. A method according to claim 11, wherein said still pictureinformation is inserted in an audio band corresponding only to aspecific still picture.
 14. A method according to claim 1, wherein saidstill picture information is transmitted by means other than a radiowave, by which said still pictures are transmitted.
 15. A methodaccording to claim 14, wherein said still picture information istransmitted via a communication line.
 16. A method according to claim15, wherein said still picture information is transmitted via the samecommunication line as said still pictures.
 17. A method according toclaim 5, wherein a menu of still pictures which have said relationshipwith said reference still picture is displayed.
 18. A method oftransmitting a plurality of still pictures by a time-division stillpicture broadcast system, including the steps of determining a stillpicture to serve as a reference still picture, selecting a still picturewhich has a relationship with said reference still picture, anddisplaying the order of said still pictures and the total number ofstill pictures repeatedly transmitted as still picture information. 19.A method of transmitting a plurality of still pictures by atime-division still picture broadcast system, including the steps ofdetermining a still picture to serve as a reference still picture,selecting a still picture which has a relationship with said referencestill picture, and appending still picture information to saidtransmitted still pictures, said still picture information beingdisplayed at a receiver end only on a specific still picture among thetransmitted still pictures.
 20. A method of transmitting a plurality ofstill pictures by a time-division still picture broadcast system,including the steps of determining a still picture to serve as areference still picture, selecting a still picture which has arelationship with said reference still picture, repeatedly transmittingsaid reference still picture, a further reference still picture which isselected according to its relationship with said reference stillpicture, and a still picture having said relationship with said furtherreference still picture, and displaying a menu of said still pictureswhich are selectable according to their relationship with said furtherreference still picture.